Cu incorporation efficiency to the ZnO lattice in nanoparticles
synthesized by an aqueous solution method
A. Iribarren,*, E. Hernández-Rodríguez
Instituto de Ciencia y Tecnología de Materiales, Universidad de La Habana, Zapata y G,
Vedado, Plaza, La Habana 10400, Cuba.
*Corresponding autor. E-mail: augusto@imre.oc.uh.cu, a_iribarren@yahoo.com
ZnO and Cu-doped ZnO nanoparticles were obtained by chemical synthesis in
aqueous media. Structural analysis gave the dominant presence of wurtzite ZnO phase
forming a solid solution Zn1-xCuxO. For high Cu doping CuO phase is also present. The
diffraction peaks are shifted either right or left respect the ZnO powder pattern
according to the Cu concentration, which indicates changes in the lattice size. For low
Cu concentration the lattice shrinks due to Cu atoms substitute Zn atoms. For high Cu
concentration the lattice enlarges due to predominance of interstitial Cu. From
elemental analysis we determined and analyzed the incorporation efficiency of Cu
atoms in Zn1-xCuxO as a function of the Cu concentration in the precursor dissolution.
Combining structural and chemical results we described the Cu/Zn precursor
concentrations rw in which the solid solution of Cu in ZnO is predominant. In the region
located at rw > 0.2–0.3 it is no longer valid. For Cu/Zn precursor concentration rw > 0.3
interstitial Cu dominates, and some amount of copper oxide appears. The effective size
of nanoparticles decreases as the Cu concentration increases.